Different non-surgical treatments of obstructive vascular disease are known. One of the first successful procedures receiving widespread acceptance was the use of a flexible catheter having a distensible balloon at its distal end. This so-called dilatation catheter is guided through an obstruction in the blood vessel and pressure is applied to the balloon, causing it to expand and compress lesions in the obstructed vessel.
The initial encouraging results produced with balloon catheters led Gruentzig to extend this technique to use in coronary arteries. A review of the use of balloon catheters for treatment of obstructive vascular disease in coronary arteries is presented in chapter 15 of Cardiovascular Procedures Diagnostic Techniques and Therapeutic Procedures, by Tilkian and Daily, C. V. Mosby Company, 1986, pp. 328-376. The chapter 15 disclosure of this text is incorporated herein by reference.
The method steps in conducting an angioplasty procedure are discussed in detail in the aforementioned text. Briefly, a guiding catheter is inserted and positioned so that the dilatation catheter can be guided into the region of blocked or reduced blood flow. A guidewire is inserted beyond the balloon catheter and manipulated by the physician until the guidewire enters the blocked blood vessel. The process of introducing the guidewire into an appropriate vessel can be very difficult, especially if the obstruction is complete or nearly so. The guidewire has such a small diameter and is so flexible it often buckles on impact with the obstruction.
Even if the physician successfully advances the guidewire through the obstruction, when the physician attempts to push the balloon through the obstruction, the diameter of the balloon may be such that the insertion is difficult or impossible. This is especially true, when deposits within the blood vessel that are blocking blood flow are rigid and do not yield to forces exerted by the balloon tip.